The data are scattered, that is, points here and there in latitude and longitude. The data have to be gridded before can use functions like viewshed, los2, contourfm, etc. We do not yet have a function to do this. However, there is an example that shows the kind of processing that is needed. See the following code:
load seamount
lon = x;
lat = y;
delta = 0.01;
loni = (210.8 : delta : 211.8);
lati = (-48.5 : delta : -47.9)';
Zi = griddata(lon, lat, z, loni, lati);
R = makerefmat(loni(1), lati(1), delta, delta);
figure('Color','white')
worldmap(Zi, R)
geoshow(Zi, R, 'DisplayType', 'surface')
